Fungal diseases represent a major threat to economically important agricultural crops. The yield of plants, for example, cotton, coffee, sugar cane, sunflower, corn, soybean and wheat, are adversely impacted by fungal diseases. Soybean rust is one of the fungal diseases caused by Phakopsora pachyrhizi. Soybean rust has been known to drastically reduce yields. Yield loss up to 80% has been reported. It could have a major impact on both total soybean production and production costs. Alternaria is also one of the fungal diseases caused by Alternaria species. Alternaria causes significant yield losses of sunflower in hot and humid areas. Yield loss up to 90% has been reported in subtropical areas. Therefore, there is a continuing need to provide a fungal composition for controlling fungal pathogens, thereby increasing the yield of plant.
Strobilurin or strobilurin-type fungicides are a well-known class of fungicides with a broad spectrum of disease control. They are extracted from the fungus Strobilurus tenacellus. They have a suppressive effect on other fungi, reducing competition for nutrients; they inhibit electron transfer between cytochrome b and cytochrome C1 at the ubiquinol oxidising site in mitochondria, disrupting metabolism and preventing growth of the target fungi. Examples of strobilurins are fluoxastrobin, mandestrobin, azoxystrobin, bifujunzhi, coumoxystrobin, enoxastrobin, flufenoxystrobin, jiaxiangjunzhi, picoxystrobin, pyraoxystrobin, pyraclostrobin, pyrametostrobin, triclopyricarb, dimoxystrobin, fenaminstrobin, metominostrobin, orysastrobin, kresoxim-methyl, trifloxystrobin, famoxadone and fenamidone.
Triazoles are a class of systemic fungicides that enter the plant and spread from the site of application to untreated or newly grown area, uprooting existing fungi or protecting the plant from future attacks. The mechanism of action of these fungicides is due to their ability to interfere with the biosynthesis of biosteroids or to inhibit the biosynthesis of ergosterol. Ergosterol is needed for membrane structure and function. It is essential for the development of functional cell walls by fungi. Therefore, application of triazoles results in abnormal fungal growth and eventually death. Examples of triazoles are azaconazole, bromuconazole, cyproconazole, diclobutrazol, difenoconazole, diniconazole, diniconazole-M, epoxiconazole, etaconazole, fenbuconazole, fluquinconazole, flusilazole, flutriafol, furconazole, furconazole-cis, hexaconazole, imibenconazole, ipconazole, metconazole, myclobutanil, penconazole, propiconazole, prothioconazole, quinconazole, simeconazole, tebuconazole, tetraconazole, triadimefon, triadimenol, triticonazole, uniconazole, amitrol, bitertanol, climbazole, clotrimazole, fluotrimazole, paclobutrazol, triazbutil and 1-(4-fluorophenyl)-2-(1H-1,2,4-triazole-1-yl)ethanone.
However, experience with the strobilurin fungicides worldwide indicates there is a high risk of development of resistant pathogen subpopulations. Resistance has been reported worldwide in an increasing number of pathogens of field crops, fruit, vegetable, and so on (Vincelli, P. 2002. QoI (Strobilurin) Fungicides: Benefits and Risks. The Plant Health Instructor. DOI: 10.1094/PHI-I-2002-0809-02. Updated, 2012). As suggested in Vincelli, P. 2002, mixing the strobilurin fungicides with other fungicides can reduce selection pressure towards resistance.
Therefore, it would be advantageous to provide a method of increasing the yield of a plant by applying a plant which is susceptible to fungal diseases caused by fungal pathogens or surrounding.